Generally, a refrigerator is a home electric appliance equipped with a storage compartment for storing food and drinks and a cold air supplier for supplying cold air to the storage compartment to keep the food and drinks more fresh. To satisfy demands from users, a refrigerator may be equipped with an ice-making machine for making ice and a dispenser for dispensing purified water, ice, sparkling water, or the like at an external side without a door of the refrigerator being opened.
As time goes by, due to various causes including repetitive use, foreign materials and germs may accumulate in such a dispenser and a passage for supplying water. Therefore, it is recommended that a passage in which foreign materials and germs accumulate is periodically cleaned through a separate device. Recently, studies on simplifying such periodical cleaning have been actively conducted.